Turbines driven by expanding gases, such as steam or combustion gases have the disadvantage of requiring very high rotational speeds for their rotors and consequently requiring great reductions in speed to adapt them to use with other much slower moving mechanisms. In the past, exhaust turbines driven by exhaust gases from internal combustion engines in motor vehicles have found practical use mostly in directly supercharging the engines of such vehicles, especially in racing cars. Hitherto, in motor vehicles, the auxiliary units have been driven from the engine by belts and pulleys. Such auxiliary units include the generator alternator, the cooling fan, the oil pump for power steering, the refrigerant compressor for air conditioning, the air compressor or power brakes of trucks and trailers and the oil pump for levelling the chassis frame in cranes and earth moving equipment. Recent investigations have shown that a great amount of power is consumed in driving these auxiliary units, thereby expending much fuel. The present invention seeks to avoid such wastage by utilizing the exhaust gases of the engine to drive a gas turbine, the extremely high output speed of which is reduced by means of the present speed-reduction transmission so that the output of the latter is sufficiently low to drive these auxiliary units and at the same time utilize the propulsive power of the exhaust gases which would otherwise be wasted. Sufficient standby electrical power is contained in the vehicle storage battery while the vehicle is halted at stop lights and other points of delay, while sufficient additional compressed air for operating the brakes during such standby periods is easily supplied by providing additional compressed air tank capacity.
The high ratio speed reduction transmission of the present invention also has the advantage over the conventional worm gear and worm wheel speed reduction transmission wherein the axes of the worm wheel shaft are necessarily perpendicular to one another, hence require a bulky casing and excessive space to accommodate such a casing. The present transmission has its input and output shafts almost coaxial with one another, hence is much more compact and requires much less space to accommodate it.